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Development of an artificial intelligence diagnostic model based on dynamic uncertain causality graphfor the differential diagnosis of dyspnea

Yang Jiao, Zhan Zhang, Ting Zhang, Wen Shi, Yan Zhu, Jie Hu, Qin Zhang

《医学前沿(英文)》 2020年 第14卷 第4期   页码 488-497 doi: 10.1007/s11684-020-0762-0

摘要: Dyspnea is one of the most common manifestations of patients with pulmonary disease, myocardial dysfunction, and neuromuscular disorder, among other conditions. Identifying the causes of dyspnea in clinical practice, especially for the general practitioner, remains a challenge. This pilot study aimed to develop a computer-aided tool for improving the efficiency of differential diagnosis. The disease set with dyspnea as the chief complaint was established on the basis of clinical experience and epidemiological data. Differential diagnosis approaches were established and optimized by clinical experts. The artificial intelligence (AI) diagnosis model was constructed according to the dynamic uncertain causality graph knowledge-based editor. Twenty-eight diseases and syndromes were included in the disease set. The model contained 132 variables of symptoms, signs, and serological and imaging parameters. Medical records from the electronic hospital records of Suining Central Hospital were randomly selected. A total of 202 discharged patients with dyspnea as the chief complaint were included for verification, in which the diagnoses of 195 cases were coincident with the record certified as correct. The overall diagnostic accuracy rate of the model was 96.5%. In conclusion, the diagnostic accuracy of the AI model is promising and may compensate for the limitation of medical experience.

关键词: knowledge representation     uncertain     causality     graphical model     artificial intelligence     diagnosis     dyspnea    

Analyzing the nonlinear vibrational wave differential equation for the simplified model of Tower Cranes

M.R. AKBARI,D.D. GANJI,A.R. AHMADI,Sayyid H. Hashemi KACHAPI

《机械工程前沿(英文)》 2014年 第9卷 第1期   页码 58-70 doi: 10.1007/s11465-014-0289-7

摘要:

In the current paper, a simplified model of Tower Cranes has been presented in order to investigate and analyze the nonlinear differential equation governing on the presented system in three different cases by Algebraic Method (AGM). Comparisons have been made between AGM and Numerical Solution, and these results have been indicated that this approach is very efficient and easy so it can be applied for other nonlinear equations. It is citable that there are some valuable advantages in this way of solving differential equations and also the answer of various sets of complicated differential equations can be achieved in this manner which in the other methods, so far, they have not had acceptable solutions. The simplification of the solution procedure in Algebraic Method and its application for solving a wide variety of differential equations not only in Vibrations but also in different fields of study such as fluid mechanics, chemical engineering, etc. make AGM be a powerful and useful role model for researchers in order to solve complicated nonlinear differential equations.

关键词: Algebraic Method (AGM)     tower crane     oscillating system     angular frequency    

Modeling, simulation, and prediction of global energy indices: a differential approach

Stephen Ndubuisi NNAMCHI, Onyinyechi Adanma NNAMCHI, Janice Desire BUSINGYE, Maxwell Azubuike IJOMAH, Philip Ikechi OBASI

《能源前沿(英文)》 2022年 第16卷 第2期   页码 375-392 doi: 10.1007/s11708-021-0723-6

摘要: Modeling, simulation, and prediction of global energy indices remain veritable tools for econometric, engineering, analysis, and prediction of energy indices. Thus, this paper differentially modeled, simulated, and non-differentially predicated the global energy indices. The state-of-the-art of the research includes normalization of energy indices, generation of differential rate terms, and regression of rate terms against energy indices to generate coefficients and unexplained terms. On imposition of initial conditions, the solution to the system of linear differential equations was realized in a Matlab environment. There was a strong agreement between the simulated and the field data. The exact solutions are ideal for interpolative prediction of historic data. Furthermore, the simulated data were upgraded for extrapolative prediction of energy indices by introducing an innovative model, which is the synergy of deflated and inflated prediction factors. The innovative model yielded a trendy prediction data for energy consumption, gross domestic product, carbon dioxide emission and human development index. However, the oil price was untrendy, which could be attributed to odd circumstances. Moreover, the sensitivity of the differential rate terms was instrumental in discovering the overwhelming effect of independent indices on the dependent index. Clearly, this paper has accomplished interpolative and extrapolative prediction of energy indices and equally recommends for further investigation of the untrendy nature of oil price.

关键词: energy indices     differential model     normalization     simulation     inflation/deflation     predictive factor and prediction rate    

Kinetic model for hydroisomerization reaction of C-aromatics

XU Ouguan, SU Hongye, JIN Xiaoming, CHU Jian

《化学科学与工程前沿(英文)》 2008年 第2卷 第1期   页码 10-16 doi: 10.1007/s11705-008-0015-2

摘要: Based on the reported reaction networks, a novel six-component hydroisomerization reaction network with a new lumped species including C-naphthenes and C-paraffins is proposed and a kinetic model for a commercial unit is also developed. An empirical catalyst deactivation function is incorporated into the model accounting for the loss in activity because of coke formation on the catalyst surface during the long-term operation. The Runge-Kutta method is used to solve the ordinary differential equations of the model. The reaction kinetic parameters are benchmarked with several sets of balanced plant data and estimated by the differential variable metric optimization method (BFGS). The kinetic model is validated by an industrial unit with sets of plant data under different operating conditions and simulation results show a good agreement between the model predictions and the plant observations.

关键词: ordinary differential     Runge-Kutta     catalyst deactivation     C-paraffins     optimization    

Tuned reactive power dispatch through modified differential evolution technique

S. BISWAS (RAHA), N. CHAKRABORTY

《能源前沿(英文)》 2012年 第6卷 第2期   页码 138-147 doi: 10.1007/s11708-012-0188-8

摘要: This paper explores the capability of modified differential evolution (MDE) technique for solving the reactive power dispatch (RPD) problem. The proposed method is based on the basic differential evolution (DE) technique with a few modifications made into it. DE is one of the strongest optimization techniques though it suffers from the problem of slow convergence while global minima appear. The proposed modifications are tried to resolve the problem. The RPD problem mainly defines loss minimization with stable voltage profile. To solve the RPD problem, the generator bus voltage, transformer tap setting and shunt capacitor placements are controlled by the MDE approach. In this paper, IEEE 14-bus and IEEE 30-bus systems are chosen for MDE implementation. The applied modification show much improved result in comparison to normal DE technique. Comparative study with other soft-computing technique including DE validates the effectiveness of the proposed method.

关键词: reactive power dispatch (RPD)     modified differential evolution (MDE)     differential evolution algorithm with localizations around the best vector (DELB)    

Review of MEMS differential scanning calorimetry for biomolecular study

Shifeng YU, Shuyu WANG, Ming LU, Lei ZUO

《机械工程前沿(英文)》 2017年 第12卷 第4期   页码 526-538 doi: 10.1007/s11465-017-0451-0

摘要:

Differential scanning calorimetry (DSC) is one of the few techniques that allow direct determination of enthalpy values for binding reactions and conformational transitions in biomolecules. It provides the thermodynamics information of the biomolecules which consists of Gibbs free energy, enthalpy and entropy in a straightforward manner that enables deep understanding of the structure function relationship in biomolecules such as the folding/unfolding of protein and DNA, and ligand bindings. This review provides an up to date overview of the applications of DSC in biomolecular study such as the bovine serum albumin denaturation study, the relationship between the melting point of lysozyme and the scanning rate. We also introduce the recent advances of the development of micro-electro-mechanic-system (MEMS) based DSCs.

关键词: differential scanning calorimetry     biomolecule     MEMS     thermodynamic    

Stress induced polarization switching and coupled hysteretic dynamics in ferroelectric materials

Linxiang WANG, Roderick MELNIK, Fuzai LV

《机械工程前沿(英文)》 2011年 第6卷 第3期   页码 287-291 doi: 10.1007/s11465-011-0230-2

摘要:

The dynamic responses of ferroelectric materials upon external mechanical and electrical stimulations are inherently nonlinear and coupled. In the current paper, a macroscopic differential model is constructed for the coupled hysteretic dynamics via modeling the orientation switching induced in the materials. A non-convex potential energy is constructed with both mechanic and electric field contributions. The governing equations are formulated as nonlinear ordinary differential equations by employing the Euler-Lagrange equation, and can be easily recast into a state space form. Hysteresis loops associated with stress induced polarization switching and butterfly-shaped behavior in ferroelectric materials are also successfully captured. The effects of mechanical loadings on the electrically induced switching are numerically investigated, as well as the mechanically-induced switching with various bias electric fields.

关键词: differential model     state space     electromechanical switching     butterfly effects     hysteresis    

Solving multi-objective optimal power flow problem considering wind-STATCOM using differential evolution

Belkacem MAHDAD, K. SRAIRI

《能源前沿(英文)》 2013年 第7卷 第1期   页码 75-89 doi: 10.1007/s11708-012-0222-x

摘要: In this paper, a simple strategy based differential evolution was proposed for solving the problem of multi-objective environmental optimal power flow considering a hybrid model (Wind-Shunt-FACTS). The DE algorithm optimized simultaneously a combined vector control based active power of wind sources and reactive power of multi STATCOM exchanged with the electrical power system to minimize fuel cost and emissions. The proposed strategy was examined and applied to the standard IEEE 30-bus with smooth cost function to solve the problem of security environmental economic dispatch considering multi distributed hybrid model based wind and STATCOM controllers. In addition, the proposed approach was validated on a large practical electrical power system 40 generating units considering valve point effect. Simulation results demonstrate that choosing the installation of multi type of FACTS devices in coordination with many distributed wind sources is a vital research area.

关键词: differential evolution     multi-objective function     optimal power flow     economic dispatch     valve point effect     environment     wind source     STATCOM    

Cluster voltage control method for “Whole County” distributed photovoltaics based on improved differential

《能源前沿(英文)》   页码 782-795 doi: 10.1007/s11708-023-0905-8

摘要: China is vigorously promoting the “whole county promotion” of distributed photovoltaics (DPVs). However, the high penetration rate of DPVs has brought problems such as voltage violation and power quality degradation to the distribution network, seriously affecting the safety and reliability of the power system. The traditional centralized control method of the distribution network has the problem of low efficiency, which is not practical enough in engineering practice. To address the problems, this paper proposes a cluster voltage control method for distributed photovoltaic grid-connected distribution network. First, it partitions the distribution network into clusters, and different clusters exchange terminal voltage information through a “virtual slack bus.” Then, in each cluster, based on the control strategy of “reactive power compensation first, active power curtailment later,” it employs an improved differential evolution (IDE) algorithm based on Cauchy disturbance to control the voltage. Simulation results in two different distribution systems show that the proposed method not only greatly improves the operational efficiency of the algorithm but also effectively controls the voltage of the distribution network, and maximizes the consumption capacity of DPVs based on qualified voltage.

关键词: distributed photovoltaics (DPVs)     cluster partitioning     improved differential evolution algorithm     voltage control     consumption capacity of distributed photovoltaics    

Scrutiny of non-linear differential equations Euler-Bernoulli beam with large rotational deviation by

M. R. AKBARI,M. NIMAFAR,D. D. GANJI,M. M. AKBARZADE

《机械工程前沿(英文)》 2014年 第9卷 第4期   页码 402-408 doi: 10.1007/s11465-014-0316-8

摘要:

The kinematic assumptions upon which the Euler-Bernoulli beam theory is founded allow it to be extended to more advanced analysis. Simple superposition allows for three-dimensional transverse loading. Using alternative constitutive equations can allow for viscoelastic or plastic beam deformation. Euler-Bernoulli beam theory can also be extended to the analysis of curved beams, beam buckling, composite beams and geometrically nonlinear beam deflection. In this study, solving the nonlinear differential equation governing the calculation of the large rotation deviation of the beam (or column) has been discussed. Previously to calculate the rotational deviation of the beam, the assumption is made that the angular deviation of the beam is small. By considering the small slope in the linearization of the governing differential equation, the solving is easy. The result of this simplification in some cases will lead to an excessive error. In this paper nonlinear differential equations governing on this system are solved analytically by Akbari-Ganji’s method (AGM). Moreover, in AGM by solving a set of algebraic equations, complicated nonlinear equations can easily be solved and without any mathematical operations such as integration solving. The solution of the problem can be obtained very simply and easily. Furthermore, to enhance the accuracy of the results, the Taylor expansion is not needed in most cases via AGM manner. Also, comparisons are made between AGM and numerical method (Runge-Kutta 4th). The results reveal that this method is very effective and simple, and can be applied for other nonlinear problems.

关键词: AGM     critical load of columns     large deformations of beam     nonlinear differential equation    

Solving nonlinear differential equations of Vanderpol, Rayleigh and Duffing by AGM

null

《机械工程前沿(英文)》 2014年 第9卷 第2期   页码 177-190 doi: 10.1007/s11465-014-0288-8

摘要:

In the present paper, three complicated nonlinear differential equations in the field of vibration, which are Vanderpol, Rayleigh and Duffing equations, have been analyzed and solved completely by Algebraic Method (AGM). Investigating this kind of equations is a very hard task to do and the obtained solution is not accurate and reliable. This issue will be emerged after comparing the achieved solutions by numerical method (Runge-Kutte 4th). Based on the comparisons which have been made between the gained solutions by AGM and numerical method, it is possible to indicate that AGM can be successfully applied for various differential equations particularly for difficult ones. The results reveal that this method is not only very effective and simple, but also reliable, and can be applied for other complicated nonlinear problems.

关键词: Algebraic Method (AGM)     Angular Frequency     Vanderpol     Rayleigh     Duffing    

An improved chaotic hybrid differential evolution for the short-term hydrothermal scheduling problem

Tahir Nadeem MALIK,Salman ZAFAR,Saaqib HAROON

《信息与电子工程前沿(英文)》 2015年 第16卷 第5期   页码 404-417 doi: 10.1631/FITEE.1400189

摘要: Short-term hydrothermal scheduling (STHTS) is a non-linear and complex optimization problem with a set of operational hydraulic and thermal constraints. Earlier, this problem has been addressed by several classical techniques; however, due to limitations such as non-linearity and non-convexity in cost curves, artificial intelligence tools based techniques are being used to solve the STHTS problem. In this paper an improved chaotic hybrid differential evolution (ICHDE) algorithm is proposed to find an optimal solution to this problem taking into account practical constraints. A self-adjusted parameter setting is obtained in differential evolution (DE) with the application of chaos theory, and a chaotic hybridized local search mechanism is embedded in DE to effectively prevent it from premature convergence. Furthermore, heuristic constraint handling techniques without any penalty factor setting are adopted to handle the complex hydraulic and thermal constraints. The superiority and effectiveness of the developed methodology are evaluated by its application in two illustrated hydrothermal test systems taken from the literature. The transmission line losses, prohibited discharge zones of hydel plants, and ramp rate limits of thermal plants are also taken into account. The simulation results reveal that the proposed technique is competent to produce an encouraging solution as compared with other recently established evolutionary approaches.

关键词: Valve-point effect     Prohibited discharge zones     Differential evolution     Chaotic sequences     Constraint handling    

Acetylated HOXB9 at lysine 27 is of differential diagnostic value in patients with pancreatic ductal

Xiaoran Sun, Jiagui Song, Jing Zhang, Jun Zhan, Weigang Fang, Hongquan Zhang

《医学前沿(英文)》 2020年 第14卷 第1期   页码 91-100 doi: 10.1007/s11684-019-0696-6

摘要: Pancreatic ductal adenocarcinoma (PDAC) is the ninth most common human malignancy and the sixth leading cause of cancer-related death in China. AcK27-HOXB9 is a newly identified HOXB9 post-transcriptional modification that can predict the outcome in lung adenocarcinoma and colon cancer well. However, the role of AcK27-HOXB9 in PDAC is unclear. The present study aims to investigate the differential diagnostic role of patients with AcK27-HOXB9 PDAC. Tissue microarrays consisting of 162 pancreatic tumor tissue samples from patients with PDAC and paired normal subjects were used to examine HOXB9 and AcK27-HOXB9 levels and localizations by immunohistochemical analysis and Western blot assay, respectively. HOXB9 was upregulated ( <0.0001), and AcK27-HOXB9 ( =0.0023) was downregulated in patients with PDAC. HOXB9 promoted ( =0.0115), while AcK27-HOXB9 ( =0.0279) inhibited PDAC progression. AcK27-HOXB9 predicted favorable outcome in patients with PDAC ( =0.0412). AcK27-HOXB9 also suppressed PDAC cell migration in a cell migration assay. The results of this study showed that HOXB9 promoted and AcK27-HOXB9 suppressed PDAC progression. The determination of ratio between HOXB9 and AcK27-HOXB9 exhibited potential diagnostic value in patients with PDAC.

关键词: HOXB9     AcK27-HOXB9     PDAC    

hepatobiliary scintigraphy in combination with determination of bilirubin from duodenal drainage in differential

Sheng-Xuan LIU, Zhi-Hua HUANG

《医学前沿(英文)》 2010年 第4卷 第3期   页码 342-345 doi: 10.1007/s11684-010-0099-1

摘要: The aim of this study was to investigate the value of technetium etifenin injection ( Tc-EHIDA) hepatobiliary scintigraphy in combination with determination of bilirubin from duodenal drainage in differential diagnosis between infantile hepatitis syndrome and biliary atresia. Tc-EHIDA hepatobiliary scintigraphy in combination with duodenal fluid examination was used for evaluation in 84 infants with persistent infantile jaundice. For diagnosing biliary atresia, the sensitivity and specificity of scintigraphy were 100% and 74.5%, respectively; the sensitivity and specificity of scintigraphy in combination with duodenal fluid examination were 100% and 100%, respectively. In conclusion, hepatobiliary scintigraphy, which is a noninvasive, safe, valuable examination method, in combination with examination of duodenal fluid, is of value for the differential diagnosis between infantile hepatitis syndrome and biliary atresia.

关键词: jaundice     radionuclide hepatobiliary scintigraphy     duodenal drainage    

Analysis of differential expression of genes induced by ethephon in elongating internodes of maize plants

Xiaoyi WEI,Weiqiang ZHANG,Qian ZHANG,Pei SUN,Zhaohu LI,Mingcai ZHANG,Jianmin LI,Liusheng DUAN

《农业科学与工程前沿(英文)》 2016年 第3卷 第3期   页码 263-282 doi: 10.15302/J-FASE-2016103

摘要: Plant growth regulators (PGRs) are commonly used in cereal cropping systems to restrict plant height and control lodging. Ethephon has been reported to shorten internodes and increase grain yield of maize. To analyze the transcriptomic profiles of maize internode elongation following ethephon treatment, differentially expressed genes were compared between the treatment and control samples of inbred line Zong 31 using the Affymetrix Maize Genome Array. According to the microarray data, 326 probe sets showed significant change in expression. Further research revealed that the most remarkable effects of ethephon on maize internodes elongation occurred during a 48 h period, when 89 differentially expressed genes were detected. There were dramatic change in transcript levels at 24 h and six Auxin transport genes and four gibberellin biosynthesis pathway genes were differentially expressed in Zong 31 in response to ethephon treatment. In summary, we showed that gaseous ethylene release is involved in internode meristem cell elongation through the regulation of plant hormone signaling in maize. This work provides a platform for studies in which candidate genes will be functionally tested for involvement in internode elongation.

关键词: maize     ethephon     internode elongation     microarray     qPCR    

标题 作者 时间 类型 操作

Development of an artificial intelligence diagnostic model based on dynamic uncertain causality graphfor the differential diagnosis of dyspnea

Yang Jiao, Zhan Zhang, Ting Zhang, Wen Shi, Yan Zhu, Jie Hu, Qin Zhang

期刊论文

Analyzing the nonlinear vibrational wave differential equation for the simplified model of Tower Cranes

M.R. AKBARI,D.D. GANJI,A.R. AHMADI,Sayyid H. Hashemi KACHAPI

期刊论文

Modeling, simulation, and prediction of global energy indices: a differential approach

Stephen Ndubuisi NNAMCHI, Onyinyechi Adanma NNAMCHI, Janice Desire BUSINGYE, Maxwell Azubuike IJOMAH, Philip Ikechi OBASI

期刊论文

Kinetic model for hydroisomerization reaction of C-aromatics

XU Ouguan, SU Hongye, JIN Xiaoming, CHU Jian

期刊论文

Tuned reactive power dispatch through modified differential evolution technique

S. BISWAS (RAHA), N. CHAKRABORTY

期刊论文

Review of MEMS differential scanning calorimetry for biomolecular study

Shifeng YU, Shuyu WANG, Ming LU, Lei ZUO

期刊论文

Stress induced polarization switching and coupled hysteretic dynamics in ferroelectric materials

Linxiang WANG, Roderick MELNIK, Fuzai LV

期刊论文

Solving multi-objective optimal power flow problem considering wind-STATCOM using differential evolution

Belkacem MAHDAD, K. SRAIRI

期刊论文

Cluster voltage control method for “Whole County” distributed photovoltaics based on improved differential

期刊论文

Scrutiny of non-linear differential equations Euler-Bernoulli beam with large rotational deviation by

M. R. AKBARI,M. NIMAFAR,D. D. GANJI,M. M. AKBARZADE

期刊论文

Solving nonlinear differential equations of Vanderpol, Rayleigh and Duffing by AGM

null

期刊论文

An improved chaotic hybrid differential evolution for the short-term hydrothermal scheduling problem

Tahir Nadeem MALIK,Salman ZAFAR,Saaqib HAROON

期刊论文

Acetylated HOXB9 at lysine 27 is of differential diagnostic value in patients with pancreatic ductal

Xiaoran Sun, Jiagui Song, Jing Zhang, Jun Zhan, Weigang Fang, Hongquan Zhang

期刊论文

hepatobiliary scintigraphy in combination with determination of bilirubin from duodenal drainage in differential

Sheng-Xuan LIU, Zhi-Hua HUANG

期刊论文

Analysis of differential expression of genes induced by ethephon in elongating internodes of maize plants

Xiaoyi WEI,Weiqiang ZHANG,Qian ZHANG,Pei SUN,Zhaohu LI,Mingcai ZHANG,Jianmin LI,Liusheng DUAN

期刊论文